diff options
Diffstat (limited to 'MdeModulePkg/Core/Dxe/Event/Timer.c')
| -rw-r--r-- | MdeModulePkg/Core/Dxe/Event/Timer.c | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/MdeModulePkg/Core/Dxe/Event/Timer.c b/MdeModulePkg/Core/Dxe/Event/Timer.c new file mode 100644 index 0000000..35ab587 --- /dev/null +++ b/MdeModulePkg/Core/Dxe/Event/Timer.c @@ -0,0 +1,358 @@ +/** @file
+
+ Core Timer Services
+
+Copyright (c) 2006 - 2008, Intel Corporation
+All rights reserved. This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution. The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+
+#include <DxeMain.h>
+
+//
+// Internal prototypes
+//
+/**
+ Returns the current system time.
+
+ @return The current system time
+
+**/
+STATIC
+UINT64
+CoreCurrentSystemTime (
+ VOID
+ );
+
+/**
+ Checks the sorted timer list against the current system time.
+ Signals any expired event timer.
+
+ @param CheckEvent Not used
+ @param Context Not used
+
+**/
+STATIC
+VOID
+EFIAPI
+CoreCheckTimers (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ );
+
+/**
+ Inserts the timer event.
+
+ @param Event Points to the internal structure of timer event
+ to be installed
+
+**/
+STATIC
+VOID
+CoreInsertEventTimer (
+ IN IEVENT *Event
+ );
+
+//
+// Internal data
+//
+
+STATIC LIST_ENTRY mEfiTimerList = INITIALIZE_LIST_HEAD_VARIABLE (mEfiTimerList);
+STATIC EFI_LOCK mEfiTimerLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_HIGH_LEVEL - 1);
+STATIC EFI_EVENT mEfiCheckTimerEvent;
+
+STATIC EFI_LOCK mEfiSystemTimeLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_HIGH_LEVEL);
+STATIC UINT64 mEfiSystemTime = 0;
+
+//
+// Timer functions
+//
+
+
+/**
+ Initializes timer support.
+
+**/
+VOID
+CoreInitializeTimer (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+
+ Status = CoreCreateEvent (
+ EVT_NOTIFY_SIGNAL,
+ TPL_HIGH_LEVEL - 1,
+ CoreCheckTimers,
+ NULL,
+ &mEfiCheckTimerEvent
+ );
+ ASSERT_EFI_ERROR (Status);
+}
+
+
+/**
+ Returns the current system time.
+
+ @return The current system time
+
+**/
+STATIC
+UINT64
+CoreCurrentSystemTime (
+ VOID
+ )
+{
+ UINT64 SystemTime;
+
+ CoreAcquireLock (&mEfiSystemTimeLock);
+ SystemTime = mEfiSystemTime;
+ CoreReleaseLock (&mEfiSystemTimeLock);
+ return SystemTime;
+}
+
+
+/**
+ Called by the platform code to process a tick.
+
+ @param Duration The number of 100ns elasped since the last call
+ to TimerTick
+
+**/
+VOID
+EFIAPI
+CoreTimerTick (
+ IN UINT64 Duration
+ )
+{
+ IEVENT *Event;
+
+ //
+ // Check runtiem flag in case there are ticks while exiting boot services
+ //
+
+ CoreAcquireLock (&mEfiSystemTimeLock);
+
+ //
+ // Update the system time
+ //
+
+ mEfiSystemTime += Duration;
+
+ //
+ // If the head of the list is expired, fire the timer event
+ // to process it
+ //
+
+ if (!IsListEmpty (&mEfiTimerList)) {
+ Event = CR (mEfiTimerList.ForwardLink, IEVENT, u.Timer.Link, EVENT_SIGNATURE);
+
+ if (Event->u.Timer.TriggerTime <= mEfiSystemTime) {
+ CoreSignalEvent (mEfiCheckTimerEvent);
+ }
+ }
+
+ CoreReleaseLock (&mEfiSystemTimeLock);
+}
+
+
+/**
+ Checks the sorted timer list against the current system time.
+ Signals any expired event timer.
+
+ @param CheckEvent Not used
+ @param Context Not used
+
+**/
+STATIC
+VOID
+EFIAPI
+CoreCheckTimers (
+ IN EFI_EVENT CheckEvent,
+ IN VOID *Context
+ )
+{
+ UINT64 SystemTime;
+ IEVENT *Event;
+
+ //
+ // Check the timer database for expired timers
+ //
+
+ CoreAcquireLock (&mEfiTimerLock);
+ SystemTime = CoreCurrentSystemTime ();
+
+ while (!IsListEmpty (&mEfiTimerList)) {
+ Event = CR (mEfiTimerList.ForwardLink, IEVENT, u.Timer.Link, EVENT_SIGNATURE);
+
+ //
+ // If this timer is not expired, then we're done
+ //
+
+ if (Event->u.Timer.TriggerTime > SystemTime) {
+ break;
+ }
+
+ //
+ // Remove this timer from the timer queue
+ //
+
+ RemoveEntryList (&Event->u.Timer.Link);
+ Event->u.Timer.Link.ForwardLink = NULL;
+
+ //
+ // Signal it
+ //
+ CoreSignalEvent (Event);
+
+ //
+ // If this is a periodic timer, set it
+ //
+ if (Event->u.Timer.Period) {
+
+ //
+ // Compute the timers new trigger time
+ //
+
+ Event->u.Timer.TriggerTime = Event->u.Timer.TriggerTime + Event->u.Timer.Period;
+
+ //
+ // If that's before now, then reset the timer to start from now
+ //
+ if (Event->u.Timer.TriggerTime <= SystemTime) {
+ Event->u.Timer.TriggerTime = SystemTime;
+ CoreSignalEvent (mEfiCheckTimerEvent);
+ }
+
+ //
+ // Add the timer
+ //
+
+ CoreInsertEventTimer (Event);
+ }
+ }
+
+ CoreReleaseLock (&mEfiTimerLock);
+}
+
+
+/**
+ Inserts the timer event.
+
+ @param Event Points to the internal structure of timer event
+ to be installed
+
+**/
+STATIC
+VOID
+CoreInsertEventTimer (
+ IN IEVENT *Event
+ )
+{
+ UINT64 TriggerTime;
+ LIST_ENTRY *Link;
+ IEVENT *Event2;
+
+ ASSERT_LOCKED (&mEfiTimerLock);
+
+ //
+ // Get the timer's trigger time
+ //
+
+ TriggerTime = Event->u.Timer.TriggerTime;
+
+ //
+ // Insert the timer into the timer database in assending sorted order
+ //
+
+ for (Link = mEfiTimerList.ForwardLink; Link != &mEfiTimerList; Link = Link->ForwardLink) {
+ Event2 = CR (Link, IEVENT, u.Timer.Link, EVENT_SIGNATURE);
+
+ if (Event2->u.Timer.TriggerTime > TriggerTime) {
+ break;
+ }
+ }
+
+ InsertTailList (Link, &Event->u.Timer.Link);
+}
+
+
+
+
+/**
+ Sets the type of timer and the trigger time for a timer event.
+
+ @param UserEvent The timer event that is to be signaled at the
+ specified time
+ @param Type The type of time that is specified in
+ TriggerTime
+ @param TriggerTime The number of 100ns units until the timer
+ expires
+
+ @retval EFI_SUCCESS The event has been set to be signaled at the
+ requested time
+ @retval EFI_INVALID_PARAMETER Event or Type is not valid
+
+**/
+EFI_STATUS
+EFIAPI
+CoreSetTimer (
+ IN EFI_EVENT UserEvent,
+ IN EFI_TIMER_DELAY Type,
+ IN UINT64 TriggerTime
+ )
+{
+ IEVENT *Event;
+
+ Event = UserEvent;
+
+ if (Event == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if (Event->Signature != EVENT_SIGNATURE) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if (Type < 0 || Type > TimerRelative || !(Event->Type & EVT_TIMER)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ CoreAcquireLock (&mEfiTimerLock);
+
+ //
+ // If the timer is queued to the timer database, remove it
+ //
+
+ if (Event->u.Timer.Link.ForwardLink != NULL) {
+ RemoveEntryList (&Event->u.Timer.Link);
+ Event->u.Timer.Link.ForwardLink = NULL;
+ }
+
+ Event->u.Timer.TriggerTime = 0;
+ Event->u.Timer.Period = 0;
+
+ if (Type != TimerCancel) {
+
+ if (Type == TimerPeriodic) {
+ Event->u.Timer.Period = TriggerTime;
+ }
+
+ Event->u.Timer.TriggerTime = CoreCurrentSystemTime () + TriggerTime;
+ CoreInsertEventTimer (Event);
+
+ if (TriggerTime == 0) {
+ CoreSignalEvent (mEfiCheckTimerEvent);
+ }
+ }
+
+ CoreReleaseLock (&mEfiTimerLock);
+ return EFI_SUCCESS;
+}
|